Mordant-dyeing azo dyes and process of making same.



IBERNHARD RICHARD, OF BASEL, SWITZERLAND, ASSIGNOR TO THE ANILINE COLOR AND EXTRACT WORKS, FORMERLY JOHN R. GEIGY, OF BASEL, SWITZERLAND.

MORDANT-DYEING AZO DYES AND PROCESS OF MAKING SAME.

om ,mo.

No Drawing.

Specification of letters Patent.

Application filed October 1, 1910. Serial No. 584,943.

Patented May 9, 1911..

0 ch whom it may concern:

Be it known that l, Bnusnxnn Riciunn, a subject of the King of Bavaria, doctor of philosophy, residing at Basel, Switzerland, have invented certain new and usctul Impl'tiVtlt'ttlltS in New i\xl(n-dant-lf)yeing Azo Dyes and Processes of Making Same, of which the following is a specification.

My inventioi'l relates to certain new and useful im 'n'ot-en'ients in coloring matters and to the methods of preparing the same and has for its object the preparation of co oring matters by combining diazo-pnitranilin-o-sulfonic acid with oxy-carhoxylic acids of the benzene series.

The known azo coloring matter obtained from p-n'itrauilin and salicylic acid besides being ditlicult to dissolve, which renders it unsuitable for many purposes, has the further disad outage that it produces dyeings that are not fast to milling and pottinc'. I have now found that coloring matters can be obtained from p-nitranilin-o-sultonic acid and salicylic acid, as we l as its homologues, which do not possess these disadvantages.

While the diazo-p-nitranilin-o-sult'onic acid is easily decomposed and rendered un suitable for combining with the oxycarboxylic acids of the benzene series, l have discovered that diazo-p-nitranilino-sull'onic acid can be combined with oxywrarborylic acids ol the benzene series in the presence of nonalccomposing substances, :1 member of which I have l'ound do not destroy or scriously impair the diazo- -nitranilin-o-sul i'ouic acid. Among these non-tlecomposing substances which can be employed are weak alkaline solutions; or the oxids ot' magnesium, Zinc or the alkaline earths or hydroxids ot' the same. I have further discovered that even strong alkaline solutions may be employed as non 1lecomposing substances when combining diazo-p-nitraniliiro-suh lonic acid with a meta compound ol oxycarboxylic acid of the benzene series, such as m-cresotinic acid.

The following examples serve as typical examples of the way in which my invention may be practiced:

t. 23.5 kg. of the ammonium salt of pnitranilin-o-sultouic acid are diazotized with 7 kg. of sodium nitrite and 210 kg. hydrochlorie acid of 20 lit". The diazo compound thus formed is isolated and thoroughly mined with ll kg. ol salicylic acid in water tated by means of salt, filtered, pressed and dried. This dye stult' dyes wool in an acid bath orange-yellow shades which are changed by chromating to red-orange shades fast to milling and pottin".

if o-cresotinic acid is employed instead of salicylic acid, a coloring matter is obtained with the same general qualities but ol a. somewhat redder shade ol" its chromatcd dyes.

2. kg. of ni-cresotinic acid are dis solved in the quantity of soda necessary tor the formation of the neutral sodium salt. To this solution the isolated diam compound ol uitranilin sult'onic acid prepared ac cording to Example 1 is added and into the well cooled solution, an aqueous solution of 8 kg. of calcined soda is run slowly with constant; stirrin When the ctmibination complete, salt is added, the mixture is liltcrcd, pressed and dried. The dye-stult thus produced, dyes a shade upon chromcmordanted wool which is somewhat redder than that produced from the dye stull' of Example 1.

The new coloring matters t'orm orange powders soluble in water to a yellow-orange solution which on the addition of a caustic alkali turns to bluislrrcd; which are soluble in concentrated sull'uric acid to a yelloworange solution: which dye \vool orange yellow shades from an acid bath, which shades on a subsequent; treatment with chromium compounds are converted into red-orange shades possessing tastness to milling and potting and which upon reduction with stannons chlorid and hydrtazhloric acid, yield para-phenylcne-tliamin sultonic acid and a 5-amino-2-oxy-carboxylic acid.

I do not limit myself to the exact. proportions and quantities stated above but what I claim and desire to secure by lictters .lateat is:

l. The process of producing new dye st nll's by combining equimolccular proportions of diazo-p-nitraniliu-o-sull'ouic acid and o-oxycarboxylic ac' is of the benzene series.

2. The process of producing new dyestuffs by diazotizing p-nitranilin-o-sulfonic acid and combining the diazo body thus obtained with o-oxy-carboxylie acids of the benzene series in the presence of a non-decomposing substance.

3. As new products, the dye-stufis obtainable by combining equi-molecular proportions of diazo-p-nitranilin.o-sulfonic acid and o-oxy-carboxylic acids of the benzene series, forming orange powders, soluble in Water to a yellow-orange solution which on the addition of a caustic alkali turns to bluish-red; which are soluble in concentrated sulfuric acid to a yellow-orange solution; which will dye orange-yellow shades from an em /5o 1 acid bath which shades on a subsequent treatment with chromium compounds are 1 converted into red-orange shades possessing fastness to milling and potting; and which I yield upon reduction With stannous chlorid and hydrochloric acid, para-phenylene-diamin sulfonic acid and a 5-an1ino-2-oXy-carboxylic acid. v

In testimony whereof I have signed this specification in .the presenceof two subscribing Witnesses.

BERNHARD RICHARD. l Witnesses l l I Gno. GIFFORD,

l ARNO D ZUBER. 

